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.TH "RDISC6" "8" "$Date$" "rdisc6" "System Manager's Manual"
.SH NAME
rdisc \- ICMPv6 Router Discovery tool
.SH SYNOPSIS
.BR "rdisc6" " [" "-qv" "] [" "-r attempts" "] [" "-s source_ip" "]"
.BR "" "[" "-w wait_ms" "] [" "IPv6 address" "] <" "iface" ">"

.SH DESCRIPTON
.B RDisc6
is an Unix program which implements the ICMPv6 Router Discovery in
userland (it is normally done by the kernel). It is used to lookup the
list of on-link routers and IPv6 prefixes.

It can also be used to force the kernel to update the state of a given
IPv6-autoconfigured network interface.

The name of the network interface to probe routers for must be
specified.

.SH OPTIONS

.TP
.BR "\-1" " or " "\-\-single"
Exit as soon as the first advertisement is received.

.TP
.BR "\-h" " or " "\-\-help"
Display some help and exit.

.TP
.BR "\-m" " or " "\-\-multiple"
Wait for possible multiple advertisements and print all of them (default).

.TP
.BR "\-n" " or " "\-\-numeric"
If the optional parameter is not a valid IPv6 address, do not try to
resolve it as a DNS hostname.

.TP
.BR "\-q" " or " "\-\-quiet"
Only display advertised IPv6 prefixes. Display nothing in case of failure.
That is mostly useful when calling the program from a shell script.

.TP
.BR "\-r attempts" " or " "\-\-retry attempts"
Send ICMPv6 Router Discovery that many times until a reply is
received, or abort. By default, rdisc6 will try 3 times before aborting
(MAX_RTR_SOLICITATIONS from RFC2461).

.TP
.BR "\-s source_ip" " or " "\-\-source source_ip"
Specify the IPv6 address to be used as the source for the router
solicitation packets.

.TP
.BR "\-V" " or " "\-\-version"
Display program version and license and exit.

.TP
.BR "\-v" " or " "\-\-verbose"
Display verbose information. That is the default.

.TP
.BR "\-w wait_ms" " or " "\-\-wait wait_ms"
.RI "Wait " "wait_ms" " milliseconds for a response before retrying."
By default, rdisc6 waits 4 second between each attempts
(RTR_SOLICITATION_INTERVAL from RFC2461).

.PP
.RB "If " "rdisc6" " does not receive any response after the specified number"
.RI "of attempts waiting for " "wait_ms" " milliseconds each time, it will"
exit with code 2. On error, it exits with code 1.
Otherwise it exits with code 0.

.SH SECURITY
.RB "" "rdisc6" " "
.RI "must be " "setuid" " " "root" " to allow use by non "
privileged users. It will drop its root privileges before any attempt
is made to send or receive data from the network to reduce the possible
impact of a security vulnerability.

.SH "SEE ALSO"
ndisc6(8), ipv6(7)

.SH AUTHOR
R\[char233]mi Denis-Courmont <remi at remlab dot net>

http://www.remlab.net/ndisc6/
